It is inspiring to think that there are people living and working on ISS, and that there are plenty of embedded systems up there keeping it going.
One night about a month ago I took our dogs out the front to do their business and inspect the boundaries of our ¼-acre estate. It was just after dark and I thought “I wonder if I can see any satellites up there?” I looked up and almost as I did so a very bright moving object appeared on the southern horizon. I watched it traverse the sky, passing almost right overhead. It was much brighter than Venus which is usually the brightest object in the post-sunset sky. It vanished over the northern horizon in a bit over 5 minutes. At best it looked a bit more than a point source, but I never thought to get my binoculars and get a better look. It had to be the International Space Station and when I got back inside I looked up the ESA’s Where is the International Space Station? page and lo and behold it had just passed almost directly overhead.
The ESA’s page is a great resource—it shows you a map of the world showing the trajectory of the ISS—the present position and the track for the previous 1.5 hours and next 1.5 hours. Why 1.5 hours? That is the time it takes for the ISS to orbit the earth, as it travels at 28800 Km/H at 400 Km above the earth’s surface. This means that the occupants get 16 sunrises and 16 sunsets every day. (I don’t think I’ll ever moan about daylight saving time again.)
This online map is how I confirmed that it was the ISS I saw—the track passed over my part of Australia. There’s a green ellipse around it which I think shows the limits of view from earth. There is also a more detailed map that you can zoom in and out and move, which shows the precise position of the ISS above the earth in real time, changing every few seconds. In addition there is a live camera view looking down to earth, which does not seem to work very often (due to communications and other foibles) but when it does it can be quite spectacular. There’s also a wealth of other information about how it was built (the earliest bits date back to 1998) and ESA’s involvement in it.
This story continues on EE Times' sister site, Embedded.com.